A variety of products are sold in kit form for final assembly by the purchaser. Such products include furniture, toys, household and garden fixtures, and the like. Significant economies arise from marketing of such products in kit form due to lower shipping expense for a compact package of "knocked down" parts, and also through elimination of final-assembly labor during manufacture.
Some form of fastener is needed to secure the kit members together, and common wood screws are often supplied with the kit. Assembly is straightforward for anyone having proper tools and reasonable skill in the use of tools, but many purchasers do not have these attributes. Improper use of a screwdriver, for example, can cause distorted, unattractive screwheads in the assembled kit, and may also result in split or broken kit components.
Manufacturers of kit products have found there is a marketing advantage in advertising "no tools required" assembly procedures for the kit parts. The fasteners previously used in such kits, however, have not been uniformly satisfactory from the standpoint of providing a tight and secure attachment of parts, and of insuring a proper mating fit of adjacent parts which have dimensional inaccuracies. Known fasteners also tend to be expensive and relatively complex, thereby defeating the objectives of kit simplicity and economy.
One style of known fastener consists of a socket assembly which typically is made of two or three separate parts including a rotatable locking cam. A pin mates with the socket, and a screwdriver or wrench is used to rotate the cam into tight mating engagement with the pin. These fasteners perform well, but are expensive to make, and their use adds significantly to the factory cost of a furniture kit which may require dozens of individual fasteners. The kit assembler is also required to use some kind of tool to insure proper attachment of the kit components.
Other known styles of fasteners include a "no tools" arrangement when a pin mates with a wedging surface on an elongated and slotted socket member. This arrangement, however, requires the cutting of a non-circular racetrack-shaped recess in the kit part which receives the socket member, and this step adds significantly to the cost of making the kit parts. Fasteners of this type also may produce misalignment of the kit parts if a tight attachment is to be achieved.
The fastener system of this invention overcomes these problems by being economical to manufacture and install, and simple to attach and lock without use of tools by the retail purchaser. Dimensional variations of kit parts within reasonable tolerances are acommodated by the fastener system, and disassembly is also accomplished without tools if the product is to be knocked down and reassembled in a new location by the purchaser.